Breast cancer is the uncontrolled growth of abnormal cells in the milk producing glands (lobules) of the breast or in the passages (ducts) that deliver milk to the nipples.
Breast cancer can spread through the lymphatic channels to lymph nodes under the arm (axilla) or in the lower neck. Less commonly, breast cancer cells spread in the circulation via the blood stream to other parts of the body, to cause secondary breast cancer.
The size of the cancer and whether or not it has spread to the lymph nodes will determine what type of surgery is performed. The stage of the cancer describes the size of the tumour and whether it has spread. The stage of the cancer is important as it determines the best treatment options. The grade of the cancer reflects the rate of growth of the cancer cells. Grade 1 cancers tend to be slow growing and are less likely to spread. Grade 3 cancers grow more quickly. Patients with grade 3 cancers or cancers that have spread to the lymph nodes are more likely to be offered chemotherapy.
Hormone sensitive breast cancers have receptors on the cell surface (oestrogen receptors). Patients with this type of cancer benefit from hormone therapy. Some breast cancers have too many HER2 receptors on the cell surface. These cancers benefit from targeted antibody treatments.
Many patients require radiotherapy after breast cancer surgery to reduce the likelihood of recurrence.
Breast cancer is the most common cancer in the UK, accounting for about 15% of all newly diagnosed cancers.
Over 53 000 new cases are diagnosed every year.
Most breast cancer cases are diagnosed at an early stage.
1 in 8 women and 1 in 870 men will be diagnosed with breast cancer during their lifetime.
Almost half of the cases occur in ladies aged 65 and over.
The incidence has slowly increased over the last decade.
Worldwide, more than 1.68 million women were diagnosed with breast cancer in 2012.*